It is typically known that an air cleaner for intake air for an engine, which is attached to a working vehicle such as a tractor and a hydraulic excavator, centrifugally separates dust or the like sucked with outer air to prevent adhesion of the dust to a filter element, and discharges the dust, which is collected in a bottom portion of a casing, from the bottom portion through a vacuator (see, for instance, Patent Literatures 1 and 2).
The air cleaner is housed in an engine compartment along with the engine. The dust from the vacuator of the air cleaner is discharged from the engine compartment through an inclined or pipe-shaped guide member provided in the engine compartment.
In some working vehicles, the air cleaner is attached outside the engine compartment due to limitations of an installation space in the engine compartment. In this case, dust from the vacuator is directly discharged outside as long as no obstacle is present below the air cleaner.